1 files changed, 147 insertions, 23 deletions

diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
index e27dd8beb94b..5118d46702d5 100644
--- a/drivers/thunderbolt/xdomain.c
+++ b/drivers/thunderbolt/xdomain.c
@@ -18,6 +18,7 @@
 #include "tb.h"
 
 #define XDOMAIN_DEFAULT_TIMEOUT			5000 /* ms */
+#define XDOMAIN_UUID_RETRIES			10
 #define XDOMAIN_PROPERTIES_RETRIES		60
 #define XDOMAIN_PROPERTIES_CHANGED_RETRIES	10
 
@@ -222,6 +223,50 @@ static int tb_xdp_handle_error(const struct tb_xdp_header *hdr)
 	return 0;
 }
 
+static int tb_xdp_uuid_request(struct tb_ctl *ctl, u64 route, int retry,
+			       uuid_t *uuid)
+{
+	struct tb_xdp_uuid_response res;
+	struct tb_xdp_uuid req;
+	int ret;
+
+	memset(&req, 0, sizeof(req));
+	tb_xdp_fill_header(&req.hdr, route, retry % 4, UUID_REQUEST,
+			   sizeof(req));
+
+	memset(&res, 0, sizeof(res));
+	ret = __tb_xdomain_request(ctl, &req, sizeof(req),
+				   TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res),
+				   TB_CFG_PKG_XDOMAIN_RESP,
+				   XDOMAIN_DEFAULT_TIMEOUT);
+	if (ret)
+		return ret;
+
+	ret = tb_xdp_handle_error(&res.hdr);
+	if (ret)
+		return ret;
+
+	uuid_copy(uuid, &res.src_uuid);
+	return 0;
+}
+
+static int tb_xdp_uuid_response(struct tb_ctl *ctl, u64 route, u8 sequence,
+				const uuid_t *uuid)
+{
+	struct tb_xdp_uuid_response res;
+
+	memset(&res, 0, sizeof(res));
+	tb_xdp_fill_header(&res.hdr, route, sequence, UUID_RESPONSE,
+			   sizeof(res));
+
+	uuid_copy(&res.src_uuid, uuid);
+	res.src_route_hi = upper_32_bits(route);
+	res.src_route_lo = lower_32_bits(route);
+
+	return __tb_xdomain_response(ctl, &res, sizeof(res),
+				     TB_CFG_PKG_XDOMAIN_RESP);
+}
+
 static int tb_xdp_error_response(struct tb_ctl *ctl, u64 route, u8 sequence,
 				 enum tb_xdp_error error)
 {
@@ -512,7 +557,14 @@ static void tb_xdp_handle_request(struct work_struct *work)
 		break;
 	}
 
+	case UUID_REQUEST_OLD:
+	case UUID_REQUEST:
+		ret = tb_xdp_uuid_response(ctl, route, sequence, uuid);
+		break;
+
 	default:
+		tb_xdp_error_response(ctl, route, sequence,
+				      ERROR_NOT_SUPPORTED);
 		break;
 	}
 
@@ -524,9 +576,11 @@ static void tb_xdp_handle_request(struct work_struct *work)
 out:
 	kfree(xw->pkg);
 	kfree(xw);
+
+	tb_domain_put(tb);
 }
 
-static void
+static bool
 tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr,
 			size_t size)
 {
@@ -534,13 +588,18 @@ tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr,
 
 	xw = kmalloc(sizeof(*xw), GFP_KERNEL);
 	if (!xw)
-		return;
+		return false;
 
 	INIT_WORK(&xw->work, tb_xdp_handle_request);
 	xw->pkg = kmemdup(hdr, size, GFP_KERNEL);
-	xw->tb = tb;
+	if (!xw->pkg) {
+		kfree(xw);
+		return false;
+	}
+	xw->tb = tb_domain_get(tb);
 
-	queue_work(tb->wq, &xw->work);
+	schedule_work(&xw->work);
+	return true;
 }
 
 /**
@@ -740,6 +799,7 @@ static void enumerate_services(struct tb_xdomain *xd)
 	struct tb_service *svc;
 	struct tb_property *p;
 	struct device *dev;
+	int id;
 
 	/*
 	 * First remove all services that are not available anymore in
@@ -768,7 +828,12 @@ static void enumerate_services(struct tb_xdomain *xd)
 			break;
 		}
 
-		svc->id = ida_simple_get(&xd->service_ids, 0, 0, GFP_KERNEL);
+		id = ida_simple_get(&xd->service_ids, 0, 0, GFP_KERNEL);
+		if (id < 0) {
+			kfree(svc);
+			break;
+		}
+		svc->id = id;
 		svc->dev.bus = &tb_bus_type;
 		svc->dev.type = &tb_service_type;
 		svc->dev.parent = &xd->dev;
@@ -826,6 +891,55 @@ static void tb_xdomain_restore_paths(struct tb_xdomain *xd)
 	}
 }
 
+static void tb_xdomain_get_uuid(struct work_struct *work)
+{
+	struct tb_xdomain *xd = container_of(work, typeof(*xd),
+					     get_uuid_work.work);
+	struct tb *tb = xd->tb;
+	uuid_t uuid;
+	int ret;
+
+	ret = tb_xdp_uuid_request(tb->ctl, xd->route, xd->uuid_retries, &uuid);
+	if (ret < 0) {
+		if (xd->uuid_retries-- > 0) {
+			queue_delayed_work(xd->tb->wq, &xd->get_uuid_work,
+					   msecs_to_jiffies(100));
+		} else {
+			dev_dbg(&xd->dev, "failed to read remote UUID\n");
+		}
+		return;
+	}
+
+	if (uuid_equal(&uuid, xd->local_uuid)) {
+		dev_dbg(&xd->dev, "intra-domain loop detected\n");
+		return;
+	}
+
+	/*
+	 * If the UUID is different, there is another domain connected
+	 * so mark this one unplugged and wait for the connection
+	 * manager to replace it.
+	 */
+	if (xd->remote_uuid && !uuid_equal(&uuid, xd->remote_uuid)) {
+		dev_dbg(&xd->dev, "remote UUID is different, unplugging\n");
+		xd->is_unplugged = true;
+		return;
+	}
+
+	/* First time fill in the missing UUID */
+	if (!xd->remote_uuid) {
+		xd->remote_uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
+		if (!xd->remote_uuid)
+			return;
+	}
+
+	/* Now we can start the normal properties exchange */
+	queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
+			   msecs_to_jiffies(100));
+	queue_delayed_work(xd->tb->wq, &xd->get_properties_work,
+			   msecs_to_jiffies(1000));
+}
+
 static void tb_xdomain_get_properties(struct work_struct *work)
 {
 	struct tb_xdomain *xd = container_of(work, typeof(*xd),
@@ -1032,21 +1146,29 @@ static void tb_xdomain_release(struct device *dev)
 
 static void start_handshake(struct tb_xdomain *xd)
 {
+	xd->uuid_retries = XDOMAIN_UUID_RETRIES;
 	xd->properties_retries = XDOMAIN_PROPERTIES_RETRIES;
 	xd->properties_changed_retries = XDOMAIN_PROPERTIES_CHANGED_RETRIES;
 
-	/* Start exchanging properties with the other host */
-	queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
-			   msecs_to_jiffies(100));
-	queue_delayed_work(xd->tb->wq, &xd->get_properties_work,
-			   msecs_to_jiffies(1000));
+	if (xd->needs_uuid) {
+		queue_delayed_work(xd->tb->wq, &xd->get_uuid_work,
+				   msecs_to_jiffies(100));
+	} else {
+		/* Start exchanging properties with the other host */
+		queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
+				   msecs_to_jiffies(100));
+		queue_delayed_work(xd->tb->wq, &xd->get_properties_work,
+				   msecs_to_jiffies(1000));
+	}
 }
 
 static void stop_handshake(struct tb_xdomain *xd)
 {
+	xd->uuid_retries = 0;
 	xd->properties_retries = 0;
 	xd->properties_changed_retries = 0;
 
+	cancel_delayed_work_sync(&xd->get_uuid_work);
 	cancel_delayed_work_sync(&xd->get_properties_work);
 	cancel_delayed_work_sync(&xd->properties_changed_work);
 }
@@ -1089,7 +1211,7 @@ EXPORT_SYMBOL_GPL(tb_xdomain_type);
  *	    other domain is reached).
  * @route: Route string used to reach the other domain
  * @local_uuid: Our local domain UUID
- * @remote_uuid: UUID of the other domain
+ * @remote_uuid: UUID of the other domain (optional)
  *
  * Allocates new XDomain structure and returns pointer to that. The
  * object must be released by calling tb_xdomain_put().
@@ -1108,6 +1230,7 @@ struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
 	xd->route = route;
 	ida_init(&xd->service_ids);
 	mutex_init(&xd->lock);
+	INIT_DELAYED_WORK(&xd->get_uuid_work, tb_xdomain_get_uuid);
 	INIT_DELAYED_WORK(&xd->get_properties_work, tb_xdomain_get_properties);
 	INIT_DELAYED_WORK(&xd->properties_changed_work,
 			  tb_xdomain_properties_changed);
@@ -1116,9 +1239,14 @@ struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
 	if (!xd->local_uuid)
 		goto err_free;
 
-	xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t), GFP_KERNEL);
-	if (!xd->remote_uuid)
-		goto err_free_local_uuid;
+	if (remote_uuid) {
+		xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t),
+					  GFP_KERNEL);
+		if (!xd->remote_uuid)
+			goto err_free_local_uuid;
+	} else {
+		xd->needs_uuid = true;
+	}
 
 	device_initialize(&xd->dev);
 	xd->dev.parent = get_device(parent);
@@ -1282,14 +1410,12 @@ static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
 		struct tb_port *port = &sw->ports[i];
 		struct tb_xdomain *xd;
 
-		if (tb_is_upstream_port(port))
-			continue;
-
 		if (port->xdomain) {
 			xd = port->xdomain;
 
 			if (lookup->uuid) {
-				if (uuid_equal(xd->remote_uuid, lookup->uuid))
+				if (xd->remote_uuid &&
+				    uuid_equal(xd->remote_uuid, lookup->uuid))
 					return xd;
 			} else if (lookup->link &&
 				   lookup->link == xd->link &&
@@ -1299,7 +1425,7 @@ static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
 				   lookup->route == xd->route) {
 				return xd;
 			}
-		} else if (port->remote) {
+		} else if (tb_port_has_remote(port)) {
 			xd = switch_find_xdomain(port->remote->sw, lookup);
 			if (xd)
 				return xd;
@@ -1416,10 +1542,8 @@ bool tb_xdomain_handle_request(struct tb *tb, enum tb_cfg_pkg_type type,
 	 * handlers in turn.
 	 */
 	if (uuid_equal(&hdr->uuid, &tb_xdp_uuid)) {
-		if (type == TB_CFG_PKG_XDOMAIN_REQ) {
-			tb_xdp_schedule_request(tb, hdr, size);
-			return true;
-		}
+		if (type == TB_CFG_PKG_XDOMAIN_REQ)
+			return tb_xdp_schedule_request(tb, hdr, size);
 		return false;
 	}